Improvement in hot-air furnaces



itn'rTED STATES PATENT FFIC.

PERRY BAKER CLARK, OF MINNEAPOLIS, MINNESOTA.

IMPROVEMENT IN HOT-AIR FURNACES.

Specification forming part of Letters Patent No. 175,664, dated April l, 1876; application filed March 11, 1876.

and figures of reference marked thereon.

Figurel of the drawings is a representation of a longitudinal verticalsection of my furnace, and Figs. 2 and 3 are transverse vertical sectional views thereof.

The nature of my invention consists in the,

construction and arrangement of a double radiator or hot-air furnace, as will be hereinaf ter more fully set forth.

In the annexed drawing, A(see Figs. 1 and 2) represents the fire-box, with grate B and ash-pit C underneath. The fire-box A is made in the form of a horizontal cylinder, with two short pipes, E E, connecting with a top horizontal drum, D. This drum is formed of two concentric cylindrical shells, connected together, and leaving the center shell open at both sides for the passage of air to be heated. In the center of this drum Displaced the smokepipe G, (see Figs. 1 and 2,) in the form of an inverted T, the center arm communicating with the smoke-space of the drum. The outer end of the smoke-pipe G is closed by a cap, a, while the inner end communicates with the perpendicular back drum H, as shown in Fig. 1. This drum is constructed in the same manner as described for the horizontal drum D, and has an air-inlet, b, at or near the bottom, as shown in Figs. 1 and 2. In the upper end of the drum H is the smokepipe I, also made in the form of an inverted T, the center arm communicating with the chimney, and the side arms communicating with the smoke-space of the drum directly opposite the entrance, or on a line with the entrance of the pipe G. J is a damper in the end of the pipe I, which dam per, when open, admits of a direct draft through said pipe, and, when closed, the smoke is caused to circulate from top to bottom, and up again, by means of a partition, d, as shown.

By the arrangement of the T-shaped smokepipes in the top and back drums, additional heating surface is obtained. The various drums are provided with suitable cleaningholes.

What I claim as new, and desire to secure by Letters Patent, is

1. The inverted-T-shaped smoke-pipe G, in combination with the horizontal drum D and 'vertical drum H, as and for the purpose set forth.

2. The inverted-T-shaped smoke-pipe I, with damper J, in combination with the vertical drum H, having interior partition (1, as and for the purpose herein set forth.

3. The combination of the furnace A, passages E, drum D, inverted-T-shaped pipe Gr, drum H, with air-inlet b and partition d, and inverted-T-shaped pipe I, with damper J, all for the purposes herein set forth.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses.

PERRY BAKER CLARK.

Witnesses: -L. A. DUNN,

E1). T. SLINGSBY. 

